docs: def on_channel_open(self, channel):
          """This method is invoked by pika when the channel has been opened. It
          will change the state to CONNECTED, add the callbacks and setup the
          channel to start consuming.
  
          :param pika.channel.Channel channel: The channel object
  
          """
          self.logger.debug('Channel opened')
          self.set_state(self.STATE_CONNECTED)
          self.channel = channel
          self.channel.add_on_close_callback(self.on_channel_closed)
          self.channel.add_on_cancel_callback(self.on_consumer_cancelled)
          if self.publisher_confirmations:
              self.delivery_tag = 0
              self.channel.confirm_delivery(self.on_confirmation)
              self.channel.add_on_return_callback(self.on_return)
          self.callbacks.on_ready(self.name)